Mesoscale Discussion
Valid: Sun 05 Jun 2022 09:00 to Sun 05 Jun 2022 11:00 UTC
Issued: Sun 05 Jun 2022 08:39
Forecaster: TUSCHY

This MESOSCALE DISCUSSION (MD) was issued to update on current conditions.

A residual nocturnal MCS event continues to blow NE towards N Bavaria. It became more elevated during the past 2 hours as seen in decreasing winds at 1-2 km AGL at local radar stations. In addition this MCS outruns existing CAPE tongue but a weak mid-level vortex (MCV development) pushes this feature still further to the NE during the following hours. Heavy rain will be the main risk.

An outflow boundary pushed E into S Bavaria with a 4 hPa pressure rise. Latest radar data however indicates a constant weakening trend of this outflow boundary around Munich with upstream winds already backing to E-erly directions. The area E of this outflow boundary (e.g. Munich E) remains more or less unaffected with BL dewpoints already in the 15 to 18 C range. Regionally enhanced cloud coverage due to the passing boundary should mix out during the following hours and otherwise lots of diabatic heating in a well capped air mass is expected.

Therefore not much change to the anticipated level 2 event with CI forecast from W to E beyond 12Z (or rather advected thunderstorms from Switzerland/SW Germany). Upscale growth is forecast and right now we expect highest CAPE/deepest BL moisture values SE of Munich. Maturing MCS with embedded bowing segments should enter this air mass with the highest risk of extreme wind gusts S/SE of Munich (not excluding the town of Munich) and probably affecting Salzburg thereafter. Favorable CAPE/shear space was already described in the main outlook.

One note of interest are the constant signals of MCV development over SE Bavaria. In this case, extreme rainfall amounts are possible along the deformation part of this vortex with QPF amounts locally well above 60-100 l/m² in a few hours (also assisted by strong ensemble signals).

The MCS will race E towards N-CNTRL/E Austria with a slow weakening trend.